Russian President Vladimir Putin and Prime Minister Shinzo Abe enter a hall before a communication session with the crew of the International Space Station at the Kremlin in Moscow on Saturday. | REUTERS

At a news conference after their summit talks at the Kremlin in Moscow, Putin said: “What is important is to seek a solution (to the peace treaty issue) that meets (the) national interests of both sides and is mutually acceptable.”

Abe said he and Putin confirmed the two countries will work closely together toward North Korea’s denuclearization, adding, “This is the stance shared by Japan and Russia.”

Abe and Putin, who did not take questions from reporters, met amid uncertainty over whether U.S. President Donald Trump and North Korean leader Kim Jong Un will hold their first summit, and after South Korean President Moon Jae-in and Kim met earlier the same day for the second time in a month.

In their 21st face-to-face meeting, Abe and Putin discussed how to foster joint economic activities in five areas on four disputed islands held by Moscow and claimed by Japan, as agreed to last September.

The two leaders agreed to accelerate talks to create businesses in the areas, and dispatch business missions to the islands in the summer.

Japan hopes such activities will pave the way to settling a decades-long territorial row over the islands, and ultimately to the signing of a postwar peace treaty. For its part, Russia aims to attract Japanese investment to its underdeveloped Far East region.

Abe is banking on Putin, who secured another six-year term in a presidential election in March, to make a landmark decision on the contested isles, which lie off Hokkaido.

In a Friday joint interview with Kyodo News and other news agencies in St. Petersburg, Putin said a peace treaty is possible if bilateral relations deepen through planned joint economic activities.

But when it comes to the disputed islands, it is still unclear whether the two countries will be able to come up with a “special framework” that does not compromise either side’s legal position on their sovereignty.

Etorofu, Kunashiri, Shikotan and the Habomai islet group were seized by the former Soviet Union at the end of the war.

As part of humanitarian measures, Abe and Putin agreed to allow former Japanese residents of the isles to visit the graves of relatives this year. A similar visit took place for the first time last year.

Abe and Putin also confirmed how far the eight-point economic cooperation package, which Abe proposed two years ago, has advanced.

On North Korea, Abe underlined that Tokyo and Moscow will closely cooperate so that Pyongyang will “head in the right direction.”

Putin said the North Korean issue should be addressed “in a political and diplomatic manner,” as opposed to Japan’s stance of keeping “maximum pressure” on the regime with help from the United States.

Japan has been performing a delicate balancing act in pursuing improved relations with Moscow, which has been watching its ties with Western countries, particularly Japan ally the United States, deteriorate.

Deputy Chief Cabinet Secretary Kotaro Nogami, who briefed reporters, said Abe and Putin confirmed they will provide support for the success of what would be the first-ever U.S.-North Korean summit. Trump, after abruptly canceling the talks, quickly signaled they could take place as initially planned anyway on June 12 in Singapore.

Nogami also said the two leaders did not bring up the surprise inter-Korean summit held earlier Saturday.

In an attempt to boost security cooperation, the two leaders agreed on the next round of so-called two-plus-two talks involving the two countries’ foreign and defense ministers later this year following a session in March 2017 in Tokyo.

Abe and Putin did not take questions from reporters despite an initial arrangement to do so during the news conference after the summit, which started around 40 minutes behind schedule.